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1.
Coralie Coudray-Meunier Audrey Fraisse Sandra Martin-Latil Sabine Delannoy Patrick Fach Sylvie Perelle 《PloS one》2016,11(1)
Human enteric viruses are recognized as the main causes of food- and waterborne diseases worldwide. Sensitive and quantitative detection of human enteric viruses is typically achieved through quantitative RT-PCR (RT-qPCR). A nanofluidic real-time PCR system was used to develop novel high-throughput methods for qualitative molecular detection (RT-qPCR array) and quantification of human pathogenic viruses by digital RT-PCR (RT-dPCR). The performance of high-throughput PCR methods was investigated for detecting 19 human pathogenic viruses and two main process controls used in food virology. The conventional real-time PCR system was compared to the RT-dPCR and RT-qPCR array. Based on the number of genome copies calculated by spectrophotometry, sensitivity was found to be slightly better with RT-qPCR than with RT-dPCR for 14 viruses by a factor range of from 0.3 to 1.6 log10. Conversely, sensitivity was better with RT-dPCR than with RT-qPCR for seven viruses by a factor range of from 0.10 to 1.40 log10. Interestingly, the number of genome copies determined by RT-dPCR was always from 1 to 2 log10 lower than the expected copy number calculated by RT-qPCR standard curve. The sensitivity of the RT-qPCR and RT-qPCR array assays was found to be similar for two viruses, and better with RT-qPCR than with RT-qPCR array for eighteen viruses by a factor range of from 0.7 to 3.0 log10. Conversely, sensitivity was only 0.30 log10 better with the RT-qPCR array than with conventional RT-qPCR assays for norovirus GIV detection. Finally, the RT-qPCR array and RT-dPCR assays were successfully used together to screen clinical samples and quantify pathogenic viruses. Additionally, this method made it possible to identify co-infection in clinical samples. In conclusion, given the rapidity and potential for large numbers of viral targets, this nanofluidic RT-qPCR assay should have a major impact on human pathogenic virus surveillance and outbreak investigations and is likely to be of benefit to public health. 相似文献
2.
By means of dropping GA3(50 ppm) and NAA (40 ppm) on the hybrid boll-embryo culturein vitro, one F1 plant ofG. hirsutum × G. bickii was obtained; when F1 branches were grafted on upland cotton and then back-crossed with upland cotton under short-day and cooler-night condition, some BC1 seeds could be harvested. The characteristic segregation was very violent in early generation. Through 3 times of back-crossing and selecting, ten stable hybrid lines with the character of both male parent (viz. red petal-purple spot and strong fibre) and female parent (plant type, earliness, white fibre, lint length, etc.) were established. These lines were assigned as HB red flower lines (HBRL). Transference of character ofG. bickii to upland cotton was proved to be successful for the first time. These new germplasms may play an important role in both the genetic research and new cotton variety breeding. 相似文献
3.
4.
A series of strains of the homozygous speciesOenothera grandiflora (characterized by the genome BB and plastome III) were combined with plastome IV fromO. parviflora (BC-IV) by means of appropriate crosses. An incompatibility between genome B and plastome IV is expressed in the haplo- and diplophase: (1) B-IV pollen, though normally developed, is largely inactive. The extent of the inactivation varies between different strains and shows a seasonal fluctuation as determined by seed set in outcrossing and selfing experiments. (2) In most of the strains lethality of BB-IV embryos is the rule, leading to empty seeds. This can be ameliorated by including another plastome in the zygotes and developing embryos on account of the biparental plastid transmission inOenothera. It can best be demonstrated in crosses with a seed parent having normal green plastids of plastome IV and mutated chlorophyll deficient plastids from a different plastome in the pollen parent, leading to variegated progeny as well as a remainder of empty seeds. (3) In about one-half of the strains the BB-IV plants exhibit a temporary bleaching of thevirescens type. The incompatibily between genome B and plastome IV does not support the earlier assumption that plastome IV is the ancestor of plastomes II, III, and V. Instead, a precursor plastome is postulated from which plastomes II, III, and IV are descended. While plastome I can be derived from II, only plastome V can be descended from plastome IV.Deceased August 28, 1998. 相似文献
5.
Deficit irrigation is an optimization strategy for achieving sustainability of irrigated crop production. A field-study of cotton (Gossypium hirsutum L.) response to a limited water supply was conducted in an Alfisol in the southern High Plains of Texas. The objectives were to investigate cotton N uptake, canopy temperature, plant spectral index and lint yield variation under deficit irrigation and to provide information for enhancing sustainability of the water resources and Alfisols in the semi-arid environment. The experimental treatments were two deficit-irrigation levels at 50% and 75% of cotton evapotranspiration (ET). Plant and soil variables were measured 15 m apart along the center-pivot irrigation circles. The results show that cotton plants under the 50%-ET deficit irrigation level were 21% more water stressed (P < 0.05) based on the reflectance water index ratio. The 50%-ET irrigation resulted in a 25% lint yield loss with a 33% water saving compared to the higher irrigation level (75%-ET). Plant reflectance, canopy temperature, total N uptake and lint yield were correlated with normalized difference vegetative index (NDVI), soil water content (SWC), soil NO3-N concentrations and elevation (−0.69 < r < 0.72, P < 0.05, respectively). Future cotton lint yield is weighted on NDVI and water variation, quantified in a multivariate autoregressive state-space model. Increases in plant reflectance in the water band are signs of early plant water stress. Compared to the 12-year regional cotton lint yield obtained with full irrigation, the 75%-ET deficit irrigation would be agronomical, economical efficient in Alfisoils with only 7.8% of lint-yield loss from water stress but 25% of water saving for sustainable water use. 相似文献
6.
Linkage disequilibrium based association mapping is a powerful tool for dissecting the genetic basis underlying complex traits. In this study, an association mapping panel consisting of 356 representative Upland cotton cultivars was constructed, evaluated in three environments and genotyped using 381 SSRs to detect molecular markers associated with lint yield and its components. The results showed that abundant phenotypic and moderate genetic diversities existed within this germplasm panel. The population could be divided into two subpopulations, and weak relatedness was detected between pair-wise accessions. LD decayed to the background (r
2 = 0.1182, P≤0.01), r
2 = 0.1 and r
2 = 0.2 level within 12–13 cM, 17–18 cM and 3–4 cM, respectively, providing the potential for association mapping of agronomically important traits in Chinese Upland cotton. A total of 55 marker-trait associations were detected between 26 SSRs and seven lint yield traits, based on a mixed linear model (MLM) and Bonferroni correction (P≤0.05/145, −log10
P≥3.46). Of which 41 could be detected in more than one environment and 17 markers were simultaneously associated with two or more traits. Many associations were consistent with QTLs identified by linkage mapping in previous reports. Phenotypic values of alleles of each loci in 41 stably detected associations were compared, and 23 favorable alleles were identified. Population frequency of each favorable allele in historically released cultivar groups was also evaluated. The QTLs detected in this study will be helpful in further understanding the genetic basis of lint yield and its components, and the favorable alleles may facilitate future high-yield breeding by genomic selection in Upland cotton. 相似文献
7.
Plant parasitic nematodes are major pests on upland cotton worldwide and in the United States. The reniform nematode, Rotylenchulus reniformis and the southern root-knot nematode Meloidogyne incognita are some of the most damaging nematodes on cotton in the United States. Current management strategies focus on reducing nematode populations with nematicides. The objective of this research was to integrate additional fertilizer and nematicide combinations into current practices to establish economical nematode management strategies while promoting cotton yield and profit. Microplot and field trials were run to evaluate fertilizer and nematicide combinations applied at the pinhead square (PHS) and first bloom (FB) plant growth stages to reduce nematode population density and promote plant growth and yield. Cost efficiency was evaluated based on profit from lint yields and chemical input costs. Data combined from 2019 and 2020 suggested a nematicide seed treatment (ST) ST + (NH4)2SO4 + Vydate® C-LV + Max-In® Sulfur was the most effective in increasing seed cotton yields in the R. reniformis microplot trials. In R. reniformis field trials, a nematicide ST + (NH4)2SO4 + Vydate® C-LV at PHS supported the largest lint yield and profit per hectare at $1176. In M. incognita field trials, a nematicide ST + 28-0-0-5 + Vydate® C-LV + Max-In® Sulfur at PHS and FB supported the largest lint yields and profit per hectare at $784. These results suggest that combinations utilizing fertilizers and nematicides applied together across the season in addition to current fertility management show potential to promote yield and profit in R. reniformis and M. incognita infested cotton fields. 相似文献
8.
Identification and Characterization of Rhizosphere-Competent Bacteria of Wheat 总被引:20,自引:5,他引:15
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To obtain rhizosphere-competent bacteria which could subsequently be modified for the development of biological control agents, bacteria were isolated from the rhizosphere and rhizoplane of wheat and barley plants by standard techniques. Of these isolates, 60 were selected for field testing as spring wheat seed inoculants in 1985. Isolates were marked genetically for resistance to antibiotics via selection of spontaneous mutants to detect and monitor isolates in the field. Forty-three days after planting, the average log10 CFU/mg (dry weight) of roots and rhizosphere soil for the mutant isolates sampled ranged from 0 to 3.4. Twenty mutant isolates were retested in 1986. A total of 4 isolates were not detected, but the other 16 had an average root colonization value of log10 2.1 CFU and a range of log10 0.9 CFU to log10 3.2 CFU when sampled 32 days after planting. The average colonization value dropped to log10 1.1 CFU 51 days later. Some isolates detected previously were not detected in the second sampling; others had root colonization values similar to those obtained in the first sampling. Mutant isolates of rhizosphere bacteria included Bacillus pumilus, Bacillus subtilis, Pseudomonas fluorescens, Streptomyces spp., Xanthomonas maltophilia, and a saprophytic coryneform. Mixtures of isolates from different genera and species were compatible on seeds and roots. 相似文献
9.
10.
By means of dropping GA3(50 ppm) and NAA (40 ppm) on the hybrid boll-embryo culturein vitro, one F1 plant ofG. hirsutum × G. bickii was obtained; when F1 branches were grafted on upland cotton and then back-crossed with upland cotton under short-day and cooler-night condition,
some BC1 seeds could be harvested. The characteristic segregation was very violent in early generation. Through 3 times of back-crossing
and selecting, ten stable hybrid lines with the character of both male parent (viz. red petal-purple spot and strong fibre)
and female parent (plant type, earliness, white fibre, lint length, etc.) were established. These lines were assigned as HB
red flower lines (HBRL). Transference of character ofG. bickii to upland cotton was proved to be successful for the first time. These new germplasms may play an important role in both
the genetic research and new cotton variety breeding. 相似文献
11.
Iris Valentin-Bon Andrew Jacobson Steven R. Monday Peter C. H. Feng 《Applied microbiology》2008,74(4):1240-1242
Analysis of 100 bagged lettuce and spinach samples showed mean total bacterial counts of 7.0 log10 CFU/g and a broad range of <4 to 8.3 log10 CFU/g. Most probable numbers (MPN) of ≥11,000 /g coliforms were found in 55 samples, and generic Escherichia coli bacteria were detected in 16 samples, but no E. coli count exceeded 10 MPN/g. 相似文献
12.
Recovering phylogenetic relationships in lineages experiencing intense diversification has always been a persistent challenge in evolutionary studies, including in Gentiana section Chondrophyllae sensu lato (s.l.). Indeed, this subcosmopolitan taxon encompasses more than 180 mostly annual species distributed around the world. We sequenced and assembled 22 new plastomes representing 21 species in section Chondrophyllae s.l. In addition to previously released plastome data, our study includes all main lineages within the section. We reconstructed their phylogenetic relationships based on protein‐coding genes and recombinant DNA (rDNA) cistron sequences, and then investigated plastome structural evolution as well as divergence time. Despite an admittedly humble species cover overall, we recovered a well‐supported phylogenetic tree based on plastome data, and found significant discordance between phylogenetic relationships and taxonomic treatments. Our results show that G. capitata and G. leucomelaena diverged early within the section, which is then further divided into two clades. The divergence time estimation showed that section Chondrophyllae s.l. evolved in the second half of the Oligocene. We found that section Chondrophyllae s.l. had the smallest average plastome size (128 KB) in tribe Gentianeae (Gentianaceae), with frequent gene and sequence losses such as the ndh complex and its flanking regions. In addition, we detected both expansion and contraction of the inverted repeat (IR) regions. Our study suggests that plastome degradation parallels the diversification of this group, and illustrates the strong discordance between phylogenetic relationships and taxonomic treatments, which now need to be carefully revised. 相似文献
13.
Canopy photosynthesis and its relationship to plant productivity in near-isogenic cotton lines differing in leaf morphology 总被引:11,自引:1,他引:10
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A 2-year study was conducted to determine the relationships between plant canopy photosynthesis, canopy light interception, and plant productivity of cotton (Gossypium hirsutum L.) exhibiting differing leaf morphologies. The near-isogenic lines were from a single background (MD 65-11) and represented the leaf shapes Normal (small leaf lobing), Sub-Okra (intermediate leaf lobing), Okra (large leaf lobing), and Super Okra (severe leaf lobing). The F1 of a cross Normal × Okra (intermediate leaf lobing) and the F2 (segregating 1:2:1 for Normal Sub-Okra, and Okra, respectively) were also grown. Reduced plant canopies were produced by Okra and Super Okra lines, which translated into increased light penetration to the ground, and hence, in reduced canopy photosynthesis. Integrated canopy photosynthesis (ICAP) was significantly associated with light interception by the plant canopy. Part of the remaining variability in ICAP was associated with confounding factors associated with plant maturity and other unmeasured genotypic factors. Intermediate (F1 and Sub-Okra) and normal leaf types displayed the largest ICAP values in both years. Lint production was positively related to ICAP (R2 = 0.53). The combination of high ICAP values and competitive lint yields indicate that intermediate lobed leaf morphologies offer promise as productive sources of physiological variation for cotton germplasm development. 相似文献
14.
Control of Listeria spp. by Competitive-Exclusion Bacteria in Floor Drains of a Poultry Processing Plant
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Tong Zhao Teresa C. Podtburg Ping Zhao Bruce E. Schmidt David A. Baker Bruce Cords Michael P. Doyle 《Applied microbiology》2006,72(5):3314-3320
In previous studies workers determined that two lactic acid bacterium isolates, Lactococcus lactis subsp. lactis C-1-92 and Enterococcus durans 152 (competitive-exclusion bacteria [CE]), which were originally obtained from biofilms in floor drains, are bactericidal to Listeria monocytogenes or inhibit the growth of L. monocytogenes both in vitro and in biofilms at 4 to 37°C. We evaluated the efficacy of these isolates for reducing Listeria spp. contamination of floor drains of a plant in which fresh poultry is processed. Baseline assays revealed that the mean numbers of Listeria sp. cells in floor drains sampled on six different dates (at approximately biweekly intervals) were 7.5 log10 CFU/100 cm2 for drain 8, 4.9 log10 CFU/100 cm2 for drain 3, 4.4 log10 CFU/100 cm2 for drain 2, 4.1 log10 CFU/100 cm2 for drain 4, 3.7 log10 CFU/100 cm2 for drain 1, and 3.6 log10 CFU/100 cm2 for drain 6. The drains were then treated with 107 CE/ml in an enzyme-foam-based cleaning agent four times in 1 week and twice a week for the following 3 weeks. In samples collected 1 week after CE treatments were applied Listeria sp. cells were not detectable (samples were negative as determined by selective enrichment culture) for drains 4 and 6 (reductions of 4.1 and 3.6 log10 CFU/100 cm2, respectively), and the mean numbers of Listeria sp. cells were 3.7 log10 CFU/100 cm2 for drain 8 (a reduction of 3.8 log10 CFU/100 cm2), <1.7 log10 CFU/100 cm2 for drain 1 (detectable only by selective enrichment culture; a reduction of 3.3 log10 CFU/100 cm2), and 2.6 log10 CFU/100 cm2 for drain 3 (a reduction of 2.3 log10 CFU/100 cm2). However, the aerobic plate counts for samples collected from floor drains before, during, and after CE treatment remained approximately the same. The results indicate that application of the two CE can greatly reduce the number of Listeria sp. cells in floor drains at 3 to 26°C in a facility in which fresh poultry is processed. 相似文献
15.
Yinhua Jia Xiwei Sun Junling Sun Zhaoe Pan Xiwen Wang Shoupu He Songhua Xiao Weijun Shi Zhongli Zhou Baoyin Pang Liru Wang Jianguang Liu Jun Ma Xiongming Du Jun Zhu 《PloS one》2014,9(5)
Improving yield is a major objective for cotton breeding schemes, and lint yield and its three component traits (boll number, boll weight and lint percentage) are complex traits controlled by multiple genes and various environments. Association mapping was performed to detect markers associated with these four traits using 651 simple sequence repeats (SSRs). A mixed linear model including epistasis and environmental interaction was used to screen the loci associated with these four yield traits by 323 accessions of Gossypium hirsutum L. evaluated in nine different environments. 251 significant loci were detected to be associated with lint yield and its three components, including 69 loci with individual effects and all involved in epistasis interactions. These significant loci explain ∼ 62.05% of the phenotypic variance (ranging from 49.06% ∼ 72.29% for these four traits). It was indicated by high contribution of environmental interaction to the phenotypic variance for lint yield and boll numbers, that genetic effects of SSR loci were susceptible to environment factors. Shared loci were also observed among these four traits, which may be used for simultaneous improvement in cotton breeding for yield traits. Furthermore, consistent and elite loci were screened with −Log10 (P-value) >8.0 based on predicted effects of loci detected in different environments. There was one locus and 6 pairs of epistasis for lint yield, 4 loci and 10 epistasis for boll number, 15 loci and 2 epistasis for boll weight, and 2 loci and 5 epistasis for lint percentage, respectively. These results provided insights into the genetic basis of lint yield and its components and may be useful for marker-assisted breeding to improve cotton production. 相似文献
16.
Based on experimental data for the octanol-water partition coefficient (Kow) of 21 polychlorinated naphthalenes (PCNs) congeners, two types of three-dimensional QSAR (3D-QSAR) models —comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) —were established with Sybyl software. This was established to predict the Kow values of 54 additional PCN congeners and carry out a modification of CN-73 to lower its Kow significantly, simultaneously maintaining the stability and insulativity of CN-73. The contour maps of two models showed that the electrostatic field plays a dominating role in the logKow values of PCNs, and the bioconcentration of PCN decreased when -Cl atoms on the 1-, 3-, 4-, 6-, and 7-positions of PCNs were replaced with electropositive groups. Moreover, there was a positive correlation between the number of -Cl atoms on PCNs and the average logKow values of PCNs. After modification of CN-73 through the electrostatic contour maps, six types of new modified CN-73 compounds were obtained with logKow values two orders of magnitude lower than that of CN-73. Meanwhile, there was not a significant difference observed between the calculated total energy (representing stability) and energy gap (representing insulativity) of the new modified compounds when compared with those of CN-73. 相似文献
17.
Isolation and Characterization of Endophytic Colonizing Bacteria from Agronomic Crops and Prairie Plants 总被引:12,自引:1,他引:11
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Denise K. Zinniel Pat Lambrecht N. Beth Harris Zhengyu Feng Daniel Kuczmarski Phyllis Higley Carol A. Ishimaru Alahari Arunakumari Raúl G. Barletta Anne K. Vidaver 《Applied microbiology》2002,68(5):2198-2208
Endophytic bacteria reside within plant hosts without causing disease symptoms. In this study, 853 endophytic strains were isolated from aerial tissues of four agronomic crop species and 27 prairie plant species. We determined several phenotypic properties and found approximately equal numbers of gram-negative and gram-positive isolates. In a greenhouse study, 28 of 86 prairie plant endophytes were found to colonize their original hosts at 42 days postinoculation at levels of 3.5 to 7.7 log10 CFU/g (fresh weight). More comprehensive colonization studies were conducted with 373 corn and sorghum endophytes. In growth room studies, none of the isolates displayed pathogenicity, and 69 of the strains were recovered from corn or sorghum seedlings at levels of 8.3 log10 CFU/plant or higher. Host range greenhouse studies demonstrated that 26 of 29 endophytes were recoverable from at least one host other than corn and sorghum at levels of up to 5.8 log10 CFU/g (fresh weight). Long-range dent corn greenhouse studies and field trials with 17 wild-type strains and 14 antibiotic-resistant mutants demonstrated bacterial persistence at significant average colonization levels ranging between 3.4 and 6.1 log10 CFU/g (fresh weight) up to 78 days postinoculation. Three prairie and three agronomic endophytes exhibiting the most promising levels of colonization and an ability to persist were identified as Cellulomonas, Clavibacter, Curtobacterium, and Microbacterium isolates by 16S rRNA gene sequence, fatty acid, and carbon source utilization analyses. This study defines for the first time the endophytic nature of Microbacterium testaceum. These microorganisms may be useful for biocontrol and other applications. 相似文献
18.
Lint percentage is an important character of cotton yield components and it is also correlated with cotton fibre development. In this study, we used a high lint percentage variety, Baimian1, and a low lint percentage, TM-1 genetic standard for Gossypium hirsutum, as parents to construct a mapping populations in upland cotton (G. hirsutum). A quantitative trait locus/loci (QTL) analysis of lint percentage was performed by using two mapping procedures; composite interval mapping (CIM), inclusive composite interval mapping (ICIM) and the F2:3 populations in 2 years. Six main-effect QTL (M-QTL) for lint percentage (four significant and two suggestive) were detected in both years by CIM, and were located on chr. 3, chr. 19, chr. 26 and chr. 5/chr. 19. Of the six QTL, marker intervals and favourable gene sources of the significant M-QTL, qLP-3(2010) and qLP-3(2011) were consistent. These QTL were also detected by ICIM, and therefore, should preferentially be used for marker-assisted selection (MAS) of lint percentage. Another M-QTL, qLP-19(2010), was detected by two mapping procedures, and it could also be a candidate for MAS. We detected the interaction between two M-QTL and environment, and 11 epistatic QTL (E-QTL) and their interaction with environment by using ICIM. The study also found two EST-SSRs, NAU1187 and NAU1255, linked to M-QTL for lint percentage that could be candidate markers affecting cotton fibre development. 相似文献
19.
Faheem Ahmad Gregory J. Daglish Andrew W. Ridley Gimme H. Walter 《Entomologia Experimentalis et Applicata》2012,145(3):272-281
We tested, in an olfactometer, whether or not Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) responds preferentially to the volatiles that emanate from the fungi associated with cotton [Gossypium hirsutum L. (Malvaceae)] seed over those that emanate from cereals, because cereals are usually portrayed as the primary resources of these beetles. Pairwise comparisons were conducted between cotton seed, wheat (Triticum aestivum L.), and sorghum [Sorghum bicolor (L.) Moench] (both Poaceae); volatiles were tested from intact seeds and from both water and ethanol extracts. The results demonstrate that T. castaneum is attracted more strongly to cotton seeds with its lint contaminated with fungi, than to the conventional resources of this species (i.e., wheat and sorghum). Further tests prove that it is the fungus on the lint that produces the active volatiles, because the beetles did not respond to sterilized cotton lint (i.e., without the fungi typically associated with it when cotton seed is stored). Tests with five fungal cultures (each representing an unidentified species that was isolated from the field‐collected cotton lint) were variable across the cultures, with only one of them being significantly attractive to the beetles. The others were not attractive and one may even have repulsed the beetles. The results are consistent with the beetles having a strong ecological association with fungi and suggest it would be worth investigating the ecology of T. castaneum from this perspective. 相似文献
20.
Demetrius Zouzoulas Spyridon D. Koutroubas George Vassiliou Emmanuel Vardavakis 《Environmental and Experimental Botany》2009,67(1):293-303
This experiment was conducted to study the effect of high ozone concentrations on two cotton (Gossypium hirsutum L.) cultivars. Two cotton cultivars (Romanos and Allegria) were exposed to control (CF < 4 ppb O3) and 100 ppb O3. Plant exposure to ozone began eight days after emergence and was interrupted one day before removing the leaves, to calculate the leaf area. Plants were exposed to ozone 7 h/day, in closed and controlled-environment chambers, during their illumination with artificial visible light.In comparison to control plants, plants exposed to O3 showed chlorotic and necrotic patches on their leaves, increased stomatal or epidermal cell density and yellowness of cotton fibers. Elevated ozone concentration did not have a significant effect on stomatal width, total leaf thickness and thickness of histological components of leaves. Exposure to ozone concentration reduced non-glandular hair density of main leaf veins, plant height, mainstem internode length, chlorophyll content, net photosynthetic rate, stomatal conductance and length and area of bracts and petals. Elevated ozone treatment reduced the maximum length of staminal tube, anther number, pollen grain germination, leaf area, leaf dry weight, boll number, raw cotton weight, total branch length, dry weight of the mainstem–branches–bracts–carpophylls and of root dry weight. Furthermore, exposure to O3 reduced the seed weight, the lint weight, the yield, the ratio of lint weight to seed weight, the fiber strength, the micronaire, the maturity index and the fiber uniformity index values. This study shows that the exposure to high ozone concentrations mainly affected the rate of photosynthesis, raw cotton weight and strength of cotton fibers. 相似文献